Once more I drop down into the sordid, corpse-ridden world of Agatha Christie. For such a well-spoken, upper-class woman, it is surprising how many people she killed over her career. However, in this one she seems to have held back, with fewer bodies falling than usual.

We’re back in the Middle East with this Christie adventure, this time in Jordan, visiting the great ancient city of Petra. There are a few people on the trip: newly qualified doctor Sarah King, elder psychologist Dr Gerard, prominent politician Lady Westholme and, of course, Hercule Poirot himself who just so happens to be around. With them all, are the Boynton family; six Americans visiting the sights. But they are a strange bunch. The children, Lennox, Raymond, Carol and Ginevra (as well as Lennox’s wife Nadia) are all of age, in their twenties, but they live under the shadow of the colossal Mrs Boynton, a huge presence in both physicality and personality.

The family do – and always have done – exactly what they are told. Mrs Boynton seems to enjoy controlling them, like some sick game. They are financially dependent on her and have their own methods of dealing with the nasty old woman. Sarah King tries to prise some of them away, to talk and engage with someone other than their fellow Boyntons, but her efforts are short-lived and squashed by the matriarch.

One evening, however, the large Buddha-like body of Mrs Boynton is found – dead, with only a small mark on her wrist indicating a potentially fatal injection. Poirot is asked by a local officer to solve the riddle. Poirot promises that he might not find any evidence that will stand up in court, but nonetheless he will try and find out what has happened anyway. Without even any real assurance that it is murder, Poirot has twenty-four hours to point the finger.

Although it took a third of the book for the murder to happen, the first part isn’t wasted, filling us in on the crimes of this old hag and the struggles faced by her family. The characters around them are all equally horrified by the lady and so they too begin to look like suspects. There are red herrings galore, too many hypodermic needles sitting about, and no one’s timings are completely consistent. It ties up neatly at the end (I’ve seen some reviewers complaining that it’s too neat – if you don’t like the “happily ever after” touch in books, don’t read the epilogue) and I was, once again wrong. Although … not entirely. Not only has Poirot by now become something of an expert of criminals, I am getting more and more familiar with the way Christie’s mind works. I worked out a couple of plot points before they were revealed but, yes, as with the actual murderer, I was wildly off course once more.

A nice touch in this book is the idea of how Poirot’s previous adventures are recounted by other characters. It’s announced to us on numerous occasions throughout the canon that Poirot is world famous, but here his part in both The ABC Murders and Murder On The Orient Express are mentioned. In fact, the latter has the solution hinted at (although not ruined for those who have yet to read that one) and a character tries to use Poirot’s methods in that case against him.

It’s all done very well, and Christie is on top form with this one, bringing together a tight cast of characters, all of whom are equally likely to have done it when viewed from afar.